Ore concentrator



Feb. 6, '11 923.

1,444,485 J. o. THOMAS ORE CONCENTRATOR Filed July 18 1921 2 sheebs-sheet l Feb. 6, 1923. 11,444,485

J. o. THOMAS ORE CONCENTRATOR v Filed July 18, 1921 2 sheets-sheet 2 Patented Feb. 65, 11923.

units FHQE.

031E CON'OENTBATOR.

Application filed July 18,

To aZZ wh m itma concern:

Be it known that 1, JAMES O. THOMAS, a citizen of the United States residing at ancouver, in the'Province of British Columbia and Dominion of Canada, have invented a certain new and useful lmprovement in Ore Concentrators, of which the following is a specification.

My invention relates to improvements in ore concentrators of the type wherein crushed ore is first ground to a fine powder and then treated in such manner as to separate and save the precious metals and the object of my improvement is to pro 'ide novel and efiicient means for grinding the ore to a fine powder before itis subjected to the treatment, the said grinding means comprising a plurality of tapered or cone shaped grinding rollers arranged to roll within suitable grindingchambers through which the ore must pass.

Another object is to provide ore grinding mechanism in which the cone shaped rollers are disposed'in a substantially horizontal position within an annular grinding chamber having one part that rotates and another part that is stationary so that the grinding rollers will be rotated continuously and in the same direction whenthe machine is in operation.

A further object is to provide ore grinc ers comprising horizontally arranged grmd ing chambers that are substantially filled with conically shaped grinding rollers arranged with their smaller ends toward acommon center but terminating short of the center so that crushed ore or similar material that is to be ground may be fed in at the center and will be ground as it moves outwardly toward the larger ends of the rollers.

A still further object is to provide a concentrator having an amalgamation or concentrating chamber below the grinding rolls in which'the-valu'able metals may be collected, said chamber having a rotary tator therein and being provided with an outlet through which tailings may be tloated off and discharged.

Gtherand more specific objects will be apparent from the following description 1921. Serial No. 485,679.

taken in connection with the accompanying drawings.

In the drawings Figure 1 is a viewin vertical midsection of an ore grinder and concentrator constructed in accordance with my invention;

Fig. 2 is a fragmentary view in elevation of a detail of the same;

Fig. 3 is a sectional view substantially on a broken line 3, 3 of Fig. 1, showing the upper grinding chamber with half of the grinding rollers removed therefrom; and

Fig. i is a sectional view substantially on broken line 4, a of Fig. 1. 5

Like reference numerals designate like parts throughout the drawings.

Referring to the drawings, I have shown a concentrator comprising a lower section formed. of a cylindrical wall 5 supported on legs (3 and having a bottom 7 provided with grooves 8 tor the reception of relatively heavy precious metals, as gold, silver, platinum and the like, that may be separated from the ground material that passes over said bottom. The cylindrical wall 5 is provid-d with a' copper lining 10 having inclined corrugations as more clearly shown in Fig. 2, said corrugated copper lining enclosing a concentrating chamber 11 from which material may be discharged or floated of? through an outlet opening 12.

The walls 5 of the lower section serves as a support for an upper section comprising a cylindrical housing 13 having a lower grinding member 14 rigidly secured thereto the said lower grinding member havingan annular saucer like recess 15 in its upper surface that is of symmetrical shape and of greater depth toward its center so that it will receive and snugly chamber a plurality of tapered or conically shaped grinding rollers 16, the circumferential portion of the annular recess 15 being rounded as at 17 to lit the rounded ends of the grinding rollers 16.

The lower grinding member 14 is provided at a plurality of points, preferably four, with discharge passageways 18 that intersect the recess 15 at its lowermost point and that extend downwardly and inwardly through the grinding memberl i and dis a shaft 24: that projects charge into the concentrating chamber 11 near enough to the center to insure that the discharging material will be thoroughly spread out over the bottom 7 and agitated before it is discharged or floated oti'.

Disposed within the housing 13 and resting upon the lower set of grinding rollers 16 is a rotary grinding section 20 having in its bottom side an annular recess 21 of suitable shape and configuration to fit the rollers 16 and in its top side another similar recess 22 for the reception of another set of the grinding rollers 16, the lowermost peripheral portion of the upper recess 22 being connected by passageways 23 with the central portion of the bottom recess 21. The rotary section 20 rigidly secured to downwardly through and is journaled in the lower grinding member 14 and that has an agitator bar 25 fixed upon the bottom end thereof and arranged to rotate therewith said agitator bar having downwardly projecting arms 26 that just clear the bottom 7 of the concentrating chamber.

The bottom. grinding member let preferably has a hub 27 that projects upwardly into the bottom of the rotary section 20 as shown in Fig. 1, to exclude dirt and grit from the bearingot the shaft 24.

- The rotary section 20 is externally provided with a cylindrical pulley surface 28 for the reception of a driving belt 30 that passes outwardly through suitable slots in the housing 13 and connects with any suitable source of power.

Resting upon the uppermost set or": grinding rollers 16 and having a bottom surface ofsuitable shape and configuration to fit said rollers is a top grinding section 31 that is supported for vertical movement by brackets 32 that fit over upright posts 33 that are secured to the housing 13. The posts 33 prevent the top grinding section 31 from turning and such grinding section is yieldingly urged downward by compression springs 3st, the compressive force oi which maybe varied by adjustment of hand wheels 35 that areontheposts 33.

The top grinding section 31 is provided with a central opening 36 through which material, as crushed ore, may be introduced.

In operation the medial grinding section 20 is rotated by the belt 30 thus causing the rollers 16 to roll around in the grinding chamber. At the same time crushed ore and water are introduced through the opening 36 and as it works outwardly toward the periphery of the upper grinding chamber is pulverized and ground by the action of the rotating rollers 16. When the ore reaches the lowermost point in the upper grinding chamber it falls into the passageways 23 and passes downwardly and in wardly to the center of the lowermost grinding chamber in which it works outwardly and is sub ected to further grindlng and is finally conducted through the passageways 18 to the concentrating chamber 11 where the valuable heavier metals are held and the lighter tailings are floated off through the discharge openings 12.

The hand Wheels 35 may be adjusted to vary pressure under which the rollers in both the upper and lower grinding chamber operate. The rollers in the lower grinding chamber will obviously be under a greater pressure than the rollers in the upper grinding chamber because they support the weight of all parts above them in addition to being subjected to the pressure'of the springs 34.

The rollers 16 :roll smoothly in the grind-- ing chambers and wear evenly but slowly so that they will last for acomparatively long time without needing to be replaced.

The several grinding sections are supported in such a manner as to admitof relative movement 'therebetween in case large particles of material that are hard to crush get into the rollers and tend to lift the rollers instead of being crushed by them.

The material works outwardly between the rollers freely thus giving the machine a large capacity in proportionto its sizeand in proportion to the power required to operate it.

I have shown two sets of the grinding rollers 16 and found that two sets form a practi a1 and efficient grinding device, but it will be understood that eitheroneor moresets of rollers may be used as desired.

The machine is simple anddurablein construction is not expensive to manufacture is efficient in operation and will grind the ore very fine so that a maximum amount of metalmay be extracted therefrom.

The foregoing description taken in connection with the accompanying drawings clearly discloses the plan of construction and method ofoperation of this device, but, while I have shown anddescribed what I now consider to be the preferred embodiment' of the invention it will be understood that the dis: closure is merely illustrative and that such changes may be made as are within-the scope of the claims. l

What I claim is: a v

Ore grinding apparatus comprising a housing a lower grinding member fixed within said housing and having in its'upper surface symmetrical annular recess that increases in depth from the center outwardly, said lower grinding member having discharge openings that intersect the circumterential portion of said recess, conically shaped rollers freely disposed within said recess with their axes substantially horizontal, a medial grinding member mounted for rotation within said housing and having a conically shaped bottom surface arranged to rest squarely upon said rollers said rotary grinding member having conduit passageways extending from the outer portion of said upper recess to the central portion of the bottom surface thereof, a set of sonically shaped rollers freely disposed Within the upper recess of said rotary medial grinding member, and an upper fixed grinding member having a conically shaped bottom surface arranged to rest squarely on said uppermost rollers and having a centrally arranged inlet passageway for material.

In Witness whereof, I hereunto subscribe my name this 8th day of July, A. D. 1921.

J AMES 0. THOMAS. 

